metadata: add libavcodec > 54 compatibility

libavcodec55 brings some API changes, including CodecID => AVCodecID.
Add a compatibility wrapper so we can build with libavcodec >= 55.
portability: add support for Illumos

This still won't work on older Solaris systems, but modern Illumos
at least should build and run now.
metadata: more libav10 compatibility changes

Add a couple more compatibility wrappers.
metadata: get embedded cover art from video files using libavformat

Newer version of libavformat can grab cover art, so we'll go ahead
and use it.  We also need to make sure we don't confuse cover art
with a normal video stream.
metadata: get rid of some unnecessary mallocs
clients: remove FLAG_SAMSUNG_DCM10 capability

I'm not entirely sure what this flag enables.  But there are reports
that is breaks browsing on Samsung Series F TV's.  So we'll have to
disable for now, until that gets sorted out by people who actually
have Samsung TV's.
clients: add NetFront Living Connect support

Add subtitle support for NetFront™ Living Connect middleware-based
clients.  These appear to include devices from Panasonic, Philips,
Vizio, Sony, and probably more.
Wrap up version 1.1.3.
Merge branch 'master' into features

Conflicts:
	upnpglobalvars.h